Peritoneum

Excludes: Gastrointestinal Tumors of the Peritoneum (8935-8936) and Peritoneum Female Genital (M-8000-8576, 8590-8671, 8930-8934, 8940-9110 for females)

Primary Site Histology Sex Staging Type
C481-C482, C488 8000-8576, 8590-8671 1, 3-5, 9 Summary Stage only
C481-C482, C488 8930-8934, 8940-9110 1, 3-5, 9 TNM 7 and Summary Stage
C481-C482, C488 8580-8589, 8680-8799, 8821-8822, 9141, 9700-9701 <Any value> Summary Stage only
C481-C482, C488 8800-8820, 8823-8921, 9120-9136, 9142-9582 <Any value> TNM 7 and Summary Stage

If you are working with a site/histology that only summary stages and you need to directly code it, please use the SEER Summary Stage 2000 manual

Notes

C481 Specified parts of peritoneum (including omentum and mesentery) C482 Peritoneum, NOS C488 Overlapping lesion of retroperitoneum and peritoneum **Note 1:** This schema is based on the UICC chapter *Soft Tissues,* pages 157-161. * Primary sites C481, C482, and C488 are listed in the chapter heading but are not specified in the anatomic subsites in this chapter of the UICC manual; however, they are included in this schema and TNM staged if appropriate histology criteria are met **Note 2:** In addition to directly assigning TNM, Summary Stage 2000 (SS2000) must be captured. If directly assigning SS2000, use the *Retroperitoneum & Peritoneum* chapter on page 188 of the [SS2000 on-line manual](https://seer.cancer.gov/tools/ssm/ssm2000/SSSM2000-122012.pdf#page=188).

Main Data Items

Name Default Value Used for Staging NAACCR Item Required By Metadata
Clinical T <BLANK> Yes NAACCR #940 None
Clinical N <BLANK> Yes NAACCR #950 None
Clinical M <BLANK> Yes NAACCR #960 None
TNM Clin Stage Group 99 Yes NAACCR #970 None
Pathologic T <BLANK> Yes NAACCR #880 None
Pathologic N <BLANK> Yes NAACCR #890 None
Pathologic M <BLANK> Yes NAACCR #900 None
TNM Path Stage Group 99 Yes NAACCR #910 None
SSF1: Grade for Sarcomas 999 Yes NAACCR #2880 All None
SSF2: Neurovascular Invasion 988 No NAACCR #2890 None None
SSF3: Bone Invasion 988 No NAACCR #2900 None None
SSF4: Pathologic M1: Source of Pathologic Metastatic Specimen 988 No NAACCR #2910 None None
Sex 9 Yes NAACCR #220 None

Additional Data Items

Name Default Value Used for Staging NAACCR Item Required By Metadata
Year of Diagnosis <BLANK> No NAACCR #390 None
Primary Site <BLANK> Yes NAACCR #400 None
Histology <BLANK> Yes NAACCR #522 None
RX Summ Systemic/Surgery Sequence <BLANK> Yes NAACCR #1639 None
RX Summ Surgery/Radiation Sequence <BLANK> Yes NAACCR #1380 None
Regional Nodes Positive <BLANK> Yes NAACCR #820 None

Initial Context

Staging Methods

Expand All | Collapse All

TNM 7 Stage

Inclusion Table

Histology
8800-8820
8823-8934
8940-9136
9142-9582

Notes

**Note:** For Peritoneum, this table is for males only. For females and site C481-C482, C488, the histologies are 8800-8820,8823-8921,9120-9136,9142-9582 because the other histologies are in PeritoneumFemaleGen.

Start

Additional Context
Pathologic Stage Group = 90
Clinical Stage Group = 90

Next Step

  1. Parse T
  2. clin_t_prefix
    tmp_clin_t

Next Step

  1. Parse N
  2. clin_n_prefix
    tmp_clin_n

Next Step

  1. Parse M
  2. tmp_clin_m
    clin_m_prefix

Next Step

  1. Parse T
  2. tmp_path_t
    path_t_prefix

Next Step

  1. Parse N
  2. tmp_path_n
    path_n_prefix

Next Step

  1. Parse M
  2. tmp_path_m
    path_m_prefix

Next Step

  1. Determine Default T
  2. Source T
    tmp_path_t
    tmp_clin_t
    tmp_combined_t

Next Step

  1. Determine Default N
  2. tmp_combined_n
    tmp_clin_n
    tmp_path_n
    Source N

Next Step

  1. Determine Default M
  2. tmp_path_m
    tmp_combined_m
    tmp_clin_m
    Source M

Next Step

  1. SSF1
  2. mapping_of_grade

Next Step

  1. TNM 7 Stage Group
  2. Clinical Stage Group

Next Step

  1. TNM 7 Path Stage Group
  2. Pathologic Stage Group

Next Step

  1. Adjustments for No Clin or No Path
  2. tmp_combined_n
    tmp_combined_m
    Source T
    Clinical Stage Group
    Pathologic Stage Group
    Source N
    tmp_combined_t
    Source M

End

Combined Stage

Inclusion Table

Histology
8800-8820
8823-8934
8940-9136
9142-9582

Notes

**Note:** For Peritoneum, this table is for males only. For females and site C481-C482, C488, the histologies are 8800-8820,8823-8921,9120-9136,9142-9582 because the other histologies are in PeritoneumFemaleGen.

Start

Additional Context
Combined Stage Group = 90
Combined N = 90
Combined M = 90
Combined T = 90

Next Step

  1. Stop if No Clin and No Path
  2. Combined M
    Combined N
    Source T
    tmp_continue
    Combined T
    Combined Stage Group
    Source N
    Source M

Next Step

  1. Combined T No Tis
  2. Source T
    tmp_combined_t

Next Step

  1. Combined N
  2. tmp_combined_n
    Source N

Next Step

  1. Combined M
  2. tmp_combined_m
    tmp_source_m
    Source M

Next Step

  1. Determine Combined Prefix
  2. cmb_t_prefix

Next Step

  1. Determine Combined Prefix
  2. cmb_n_prefix

Next Step

  1. Determine Combined Prefix
  2. cmb_m_prefix

Next Step

  1. Concatenate T
  2. Combined T

Next Step

  1. Concatenate N
  2. Combined N

Next Step

  1. Concatenate M
  2. Combined M

Next Step

  1. TNM 7 Path Stage Group
  2. Combined Stage Group

End

Outputs

Name Default Value Description NAACCR Item Metadata
Derived Version {{ctx_alg_version}} None None
Derived SEER Clin Stage Group 88 NAACCR #3610
None
None
Derived SEER Path Stage Group 88 NAACCR #3605
None
None
Derived SEER Combined Stage Group 88 NAACCR #3614
None
None
Derived SEER Combined T 88 NAACCR #3616
None
None
Derived SEER Combined N 88 NAACCR #3618
None
None
Derived SEER Combined M 88 NAACCR #3620
None
None
Derived SEER Combined T Source <BLANK> NAACCR #3622
None
None
Derived SEER Combined N Source <BLANK> NAACCR #3624
None
None
Derived SEER Combined M Source <BLANK> NAACCR #3626
None
None